High density patching system

ABSTRACT

The present disclosure relates to high density patching system. The system includes a card housing having a front end positioned opposite from a rear end. The card housing includes top and bottom walls extending between the front and rear ends. The top and bottom walls define opposing sets of top and bottom slots. The patching system also includes a plurality of patch cords including patch plugs each having a width W 1  and a height H 1 . The patching system further includes a plurality of jack access cards adapted to be mounted in the card housing, and a rear interface module positioned at the rear end of the card housing. The jack access cards include circuit boards having top and bottom edges adapted to fit within the sets of top and bottom slots defined by the card housing. The jack access cards also include a plurality of card edge contacts positioned at a rear of each circuit board. The jack access cards further include front interface pieces having heights H 2  that are greater than two times the height H 1 , and widths W 2  that are each less than two times the width W 1 . The front interface pieces each define upper and lower patch plug ports that are vertically spaced along the height H 2  of each front interface piece. The upper and lower patch plug ports are sized and shaped to receive only a single one of the patch plugs at a time. The rear interface module includes a single row of card edge connectors adapted for providing electrical connections with the card edge contacts of the jack access cards. The rear interface module also includes an array of rear connectors including upper and lower rows of rear connectors. The array of rear connectors is electrically connected to the card edge connectors by a flexible circuit board. The rear interface module also includes a frame that spaces the card edge connectors from the rear connectors. The frame includes a rear wall defining upper and lower rows of openings that respectively receive the upper and lower rows of rear connectors.

This application is a continuation of application Ser. No. 09/293,026,filed Apr. 16, 1999, which applications are incorporated herein byreference.

FIELD OF THE INVENTION

The present invention relates generally to high density patchingsystems. More particularly, present invention relates patching systemsfor voice or data communication applications such as audio and videoentertainment applications.

BACKGROUND OF THE INVENTION

Patching systems are frequently used in data transmission applicationsto improve system flexibility and reliability. One type of existingpatching system includes a plurality of jack access cards that aremounted in a chassis. Each jack access card interfaces with a pair ofrear connectors. A first rear connector of each pair is typicallyconnected to a user's transmitter (e.g., a machine or other piece ofequipment that transmits signals or data). A second rear connector ofeach pair is typically connected to user's receiver (e.g., a machine orother piece of equipment that receives signals or data). Transmissionsfrom the transmitter enter the patching system through the first rearconnector, travel through a circuit path provided by one of the jackaccess cards, and exit the patching system through the second rearconnector. Normally, the circuit is closed. However, by inserting apatch plug into a patch port defined by the jack access card, thecircuit is opened and the transmission from the user's transmitter isdiverted through the patch plug to a secondary piece of equipment (e.g.,a back-up receiver, diagnostic equipment, equipment performingalternative functions, etc.).

Ease of use and reliability are factors relevant to the design ofpatching systems. Other factors include cost, circuit density, andinterchangeability or modularity of parts.

SUMMARY OF THE INVENTION

One aspect of the present invention relates to a jack access cardadapted for use with patch cords equipped with patch plugs each having awidth W₁ and height H₁. The jack access card includes a circuit boardhaving a front end positioned opposite from a rear end. A plurality ofcard edge contacts are positioned at the rear end of the circuit board.Upper and lower sets of spring contacts are also positioned on thecircuit board. The upper and lower sets of spring contacts each includefront contacts positioned near the front of the circuit board, andintermediate contacts positioned generally between the front contactsand the card edge contacts. A first plurality of tracings electricallyconnect selected ones of the intermediate contacts to selected ones ofthe card edge contacts. A second plurality of tracings electricallyconnect selected ones of the front contacts corresponding to the upperset of spring contacts with selected ones of the front contactscorresponding to the lower set of spring contacts. The jack access cardalso includes upper and lower sets of springs adapted to selectivelyprovide electrical connections between the front and intermediatecontacts. The jack access card further includes a front interface piecepositioned at the front of the circuit board. The front interface piecehas a height H₂ that is greater than two times the height H₁, and awidth W₂ that is less than two times the width W₁. The front interfacepiece defines upper and lower patch plug ports that are verticallyspaced along the height H₂ of the front interface piece. The upper andlower patch plug ports are sized and shaped to each receive only asingle one of the patch plugs at a time.

Another aspect of the present invention relates a rear interface modulefor a high density patching system. The rear interface module includes aframe including a front end positioned opposite from a rear end. Theframe also includes opposing top and bottom walls extending between thefront and rear ends. The frame further includes a rear wall thatinterconnects the top and bottom walls. The rear wall is located at therear end of the frame and defines two vertically spaced-apart rows ofopenings. The rear interface module also includes a single row of cardedge connectors positioned at the front end of the frame. The card edgeconnectors include a plurality and first pins that project toward therear end of the frame. The rear interface module further includes twovertically spaced-apart rows of rear connectors mounted at the rear wallof the frame. At least portions of the rear connectors extend throughthe vertically spaced-apart openings. The rear connectors include aplurality of second pins that project toward the front end of the frame.The first pins corresponding to the card edge connectors areelectrically connected to the second pins corresponding to the rearconnectors by a flexible circuit board that is positioned between thetop and bottom walls of the frame.

A further aspect of the present invention relates to a high densitypatching system. The system includes a card housing having a front endpositioned opposite from a rear end. The card housing includes top andbottom walls extending between the front and rear ends. The top andbottom walls define opposing sets of top and bottom slots. The patchingsystem also includes a plurality of patch cords including patch plugseach having a width W₁ and a height H₁. The high density patching systemfurther includes a plurality of jack access cards adapted to be mountedthrough the front end of the card housing, and a rear interface modulepositioned at the rear end of the card housing. The jack access cards ofthe patching system include circuit boards having top and bottom edgesadapted to fit within the sets of top and bottom slots defined by thecard housing. The jack access cards also include a plurality of cardedge contacts positioned at a rear of each circuit board, and a frontinterface piece positioned at a front of each circuit board. The frontinterface pieces have heights H₂ that are each greater than two timesthe height H₁, and widths W₂ that are less than two times the width W₁.The front interface pieces each define upper and lower patch plug portsthat are vertically spaced along the height H₂ of each interface piece.The upper and lower patch plug ports are sized and shaped to receiveonly a single one of the patch plugs at a time. The rear interfacemodule of the patching system includes a single row of card edgeconnectors adapted for providing electrical connections with the cardedge contacts of the jack access cards. The rear interface module alsoincludes an array of rear connectors. The array of rear connectors iselectrically connected to the card edge connectors by a flexible circuitboard. The frame of the module spaces the card edge connectors from therear connectors.

A variety of advantages of the invention will be set forth in part andthe description that follows, and in part will be apparent from thedescription, or may be learned by practicing the invention. It is to beunderstood that both the foregoing general description and the followingdetailed description are exemplary and explanatory only and are notrestrictive of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate several aspects of the inventionand together with the description, serve to explain the principles ofthe invention. A brief description of the drawings is as follows:

FIG. 1A is a top view of a high density patching system constructed inaccordance with the principles of the present invention;

FIG. 1B is a perspective view of the high density patching system ofFIG. 1A;

FIG. 2 is an exploded view of the patching system of FIG. 1B;

FIG. 3 is a perspective view of jack access card adapted for use withthe patching system of FIG. 1B;

FIG. 4 is an exploded view of the jack access card of FIG. 3;

FIG. 5 is a perspective view of the back side of one of the springholders of FIG. 4;

FIG. 6A illustrates a patch cord suitable for use with the patchingsystem of FIG. 1B;

FIG. 6B is a right end view of one of the patch plugs of the patch cordof FIG. 6A;

FIG. 6C is a top view of one of the patch plugs of the patch cord ofFIG. 6A;

FIG. 7 is a front view of the jack access card of FIG. 3;

FIG. 8 is a top view of the jack access card of FIG. 3;

FIG. 9A illustrates a normally closed circuit path of the jack accesscard of FIG. 3;

FIG. 9B illustrates an open or “patched” circuit of the jack access cardof FIG. 3;

FIG. 10 is a rear perspective view of a rear interface module suitablefor use with the high density patching system of FIG. 1B;

FIG. 11 is an exploded view of the rear interface module of FIG. 10;

FIG. 12A is a front view of a card edge connector suitable for use withthe rear interface module of FIG. 10;

FIG. 12B is a side view of the card edge connector of FIG. 12A;

FIG. 12C is a rear view of the card edge connector of FIG. 12A;

FIG. 12D is a bottom view of the card edge connector of FIG. 12A;

FIG. 13A is a rear view of a rear connector suitable for use with therear interface module of FIG. 10;

FIG. 13B is a side view of the rear connector of FIG. 13A;

FIG. 13C is a front view of the rear connector of FIG. 13A;

FIG. 13D is a bottom view of the rear connector of FIG. 13A;

FIG. 14 illustrates a flexible circuit wiring diagram for one of thecard edge connectors of the rear interface module, and its correspondingpair of rear connectors; and

FIG. 15 illustrates an alternative rear interface module constructed inaccordance with the principles of the present invention.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary aspects of the presentinvention that are illustrated in the accompanying drawings. Whereverpossible, the same reference numbers will be used throughout thedrawings to refer to the same or like parts.

FIGS. 1A, 1B and 2 illustrate a patching system 20 constructed inaccordance with the principles of the present invention. The patchingsystem 20 includes a chassis 22 including a card housing 24. Thepatching system 20 also includes a plurality of jack access cards 26adapted to be mounted in the card housing 24. The patching system 20further includes a rear interface module 28 mounted at a rear side ofthe card housing 24. As shown in FIG. 2, the jack access cards 26include rear card edge contacts 30. When the jack access cards 26 aremounted within the card housing 24, the rear card edge contacts 30 fitwithin corresponding card edge connectors 32 of the rear interfacemodule 28. In this manner, electrical connections are provided betweenthe jack access cards 26 and the rear interface module 28.

The chassis 22 includes opposing left and right sidewalls 34 _(L) and 34_(R). At the front of the chassis 22. Left and right flanges 36 _(L), 36_(R) project transversely outward from the sidewalls 34 _(L), 34 _(R).The flanges 36 _(L), 36 _(R) are adapted for use in connecting thechassis 22 to a rack (not shown). A rear support member 43 is connectedbetween the left and right side walls 34 _(L), 34 _(R) to enhance thestructural rigidity of the chassis 22.

The chassis 22 also includes opposing top and bottom walls 38 and 40that extend between the left and right sidewalls 34 _(L), 34 _(R). Thesidewalls 34 _(L), 34 _(R) and the top and bottom walls 38, 40 cooperateto form the card housing 24. The card housing defines a hollow bay 42that preferably has a width of about 19 inches and a height of about 3.5inches. As shown in FIG. 1B, the bay 42 is fully loaded with a plurality(e.g., 32) of individual jack access cards 26. The jack access cards 26are connected to upper and lower flanges of the card housing 24 byconventional fasteners ( e.g., bolts, screws, snap-fit connectors,etc.).

Referring to FIG. 2, the chassis 22 is illustrated with the jack accesscards 26 removed from the bay 42. For clarity, only one of the jackaccess cards 26 is shown exploded from the chassis 22. The illustratedjack access card 26 includes a circuit board 44 having upper and loweredges 46 and 48 adapted to slide within corresponding upper and lowerslots 50 and 52 defined by the card housing 24. As shown in FIGS. 1A, 1Band 2, the edges of the slots 50, 52 are substantially parallel andequidistant from each other along the length of the slots 50, 52.Projections 200 project transversely into the slots from the edges. Inthe embodiment illustrated in FIG. 2, sets of projections 200 correspondto each slot. Each set of projections includes two spaced-apart firstprojections and a second projection aligned between the firstprojections. The first projections extend into the slot in an oppositedirection as compared to their corresponding second projections.Preferably, the card housing 24 defines 32 pairs of the upper and lowerslots 50 and 52 such that 32 of the jack access cards 26 can be mountedin the chassis 22.

Referring to FIGS. 3 and 4, one of the jack access cards 26 isillustrated in isolation from the entire patching system 20. The jackaccess card 26 includes a front interface piece 54 defining upper andlower patch plug ports 56 and 58. The front interface piece 54 isconnected to the circuit board 44. Upper and lower sets of springs 60and 62 are secured to the board 44. The upper set of springs 60 isconnected to the circuit board 44 by an upper spring holder 64, and thelower set of springs 62 is connected to the circuit board 44 by a lowerspring holder 66. As shown in FIG. 5, the spring holders 64 and 66(which have identical configurations) include a plurality of parallelslots or channels 68 for receiving and isolating the springs 60 and 62.The upper and lower spring holders 64 and 66 are preferably fastened tothe circuit board 44 by conventional fasteners 70. The upper and lowerholders 64 and 66 also preferably include alignment pegs 72 that fitwithin corresponding alignment openings defined by the circuit board 44.

The upper and lower patch plug ports 56 and 58 are each sized and shapedto receive only a single patch plug 74 (shown in FIGS. 6A-6C) at a time.For example, the ports 56 and 58 each have a generally rectangular shapethat complements a rectangular profile (see FIG. 6B) of a single one ofthe patch plugs 74.

Referring to FIG. 6A, a patch cord 76 having patch plugs 74 isillustrated. As shown in FIG. 6B, each of the patch plugs 74 has a widthW₁ and a height H₁. Each of the patch plugs 74 also includes a housing78 having a receptacle or open end 80 (shown in FIG. 6B). A single rowof contact springs 82 is mounted in the open end 80 of each housing 78.Each housing 78 also defines two recesses 84. As will be described laterin the specification, the recesses 84 are used to assist in mechanicallysecuring the patch plugs 74 within the patch plug ports 56 and 58.

Referring to FIG. 7, the front interface piece 54 of the jack accesscard 26 has a height H₂ and a width W₂. Preferably, the height H₂ isgreater than two times the height H₁ of each patch plug 74, and thewidth W₂ is preferably less than two times the width W₁ of each patchplug 74. By selecting the width W₂ to be less than two times the widthW₁, improved circuit density can be achieved. Also, by selecting theheight H₂ to be greater than two times the height H₁, two or more of thepatch plug ports 56 and 58 can be vertically spaced or aligned along acommon vertical axis 86. This also assists in improving circuit density.The vertical axis 86 on which the patch plug ports 56 and 58 arepreferably centered, is preferably offset from a central axis 88 of thefront interface piece 54.

Referring back to FIGS. 3 and 4, the jack access card 26 also includesan upper resilient retaining member 90 corresponding to the upper patchplug port 56, and a lower resilient retaining member 92 corresponding tothe lower patch plug port 58. The upper and lower retaining members 90and 92 each have a generally cantilevered configuration and includeinwardly projecting retaining tabs 94 (best shown in FIG. 7). When oneof the patch plugs 74 is inserted within one of the patch plug ports 56and 58, the retaining tabs 94 snap within the recesses 84 of the patchplug 74 to mechanically hold the plug 74 within the plug port.

The ports 56 and 58 preferably complement the profile of each plug 74such that the plugs 74 can not be improperly inserted (i.e., insertedbackwards or up-side-down) in the ports 56 and 58. For example,referring again to FIG. 7, each of the upper and lower patch plug ports56 and 58 defines a generally rectangular recess 96 positioned oppositefrom the retaining tabs 94. Each rectangular recess 96 is configured toreceive a corresponding rectangular projection 98 that extends outwardfrom one side of each patch plug 74. As shown in FIG. 6B, the projection98 is formed between two end notches 99.

Referring to FIG. 8, the jack access card 26 also includes left andright connecting structures 100 and 102. The left and right connectingstructures 100 and 102 oppose one another and are generally parallel.Portions of the circuit board 44 and the upper and lower spring housings64 and 66 are positioned between the left and right connectingstructures 100 and 102.

Referring to FIG. 3, the right connecting structure 102 includes anupper extension 104, a lower extension 106, and an intermediateextension 108. The upper extension 104 is located above the upperretaining member 90, the lower extension 106 is located below the lowerretaining member 92, and the intermediate extension 108 is locatedbetween the upper and lower retaining members 90 and 92. Theintermediate extension 108 overlaps both of the upper and lower springhousings 64 and 66. Conventional fasteners 110 fasten the circuit board44 and the spring housings 64 and 66 between the left and rightconnecting structures 100 and 102.

Referring to FIG. 4, the card edge contacts 30 of the circuit board 44are positioned on an extension 112 that projects rearwardly from a mainbody of the circuit board 44. It will be appreciated that each card edgecontact 30 has a corresponding contact located on the opposite side ofthe rear extension 112.

Still referring to FIG. 4, the circuit board 44 includes an upper set ofspring contacts 114 and a lower set of spring contacts 116. The upperset of spring contacts 114 includes a column of front contacts 118 and acolumn of intermediate contacts 120. Similarly, the lower set of springcontacts 116 includes a column of front contacts 122 and a column ofintermediate contacts 124. The front contacts 118 and 122 are positionedadjacent to a front edge of the circuit board 44, while the intermediatecontacts 120 and 124 are positioned between the front contacts 118, 122and the card edge contacts 30.

FIGS. 9A and 9B show a representative circuit or tracing layout for thecircuit board 44. For clarity, only a single circuit path isillustrated. However, those of reasonable skill in the art willappreciate that similar circuit paths can be provided for each pair ofcard edge contacts 30.

Referring to FIG. 9A, one of the upper springs 60 and one of the lowersprings 62 are each shown in a normally closed position. With thecircuit normally closed, the springs 60 and 62 provide normal-throughfunctionality for twisted pair balanced circuit applications. Forexample, in the normal orientation of FIG. 9A, the circuit path extendsfrom one of the card edge contacts 30 through tracing 126 to one of theintermediate contacts 120. From the intermediate contact 120, thecircuit path extends through spring 60 to front contact 118. From frontcontact 118, the circuit path moves through tracing 128 to front contact122. Next, the circuit path moves through spring 62 from the frontcontact 122 to the intermediate contact 124. Finally, the circuit pathmoves through tracing 130 to another of the card edge contacts that islocated on the under side of the circuit board 44 at a position oppositefrom the originating contact 30.

When the jack access card 26 is in the normally closed position of FIG.9A, a transmission from a user's transmitter enters the patching system20 through the rear interface module 28 and travels through the circuitpath shown in FIG. 9A. After traveling through the circuit path of FIG.9A, the transmission exits the patching system 20 through the rearinterface module 28 and travels to the user's normal receiver. If it isdesired to divert the signal traveling through the jack access card 26,one of the patching plugs 74 is inserted into one of the patch plugports 56, 58. With the plug 74 inserted within one of the plug ports 56,58, the circuit path of FIG. 9A is opened and the signal is patchedthrough the patch plug 74 to an alternative piece of receivingequipment.

FIG. 9B illustrates a representative patching configuration. In FIG. 9B,one of the patch plugs 74 (with portions of the housing 78 removed toimprove the visibility of the contact springs 82) has been inserted inthe upper patch plug port 56. When the plug 74 is inserted in the upperport 56, the spring 60 is flexed away from the circuit board 44 suchthat the spring 60 disconnects from the front contact 118. Concurrently,the spring 60 makes contact with one of the contact springs 82 of thepatch plug 74. Consequently, the signal traveling through the circuitpathway is patched from the spring 60 to the patch plug 74. From thepatch plug 74, the signal travels through patch cord 76 to thealternative receiving equipment. When the user has finished patching thesignal, the plug 74 is removed from the plug port 56 and the spring 60flexes back into engagement with the front contact 118 thereby closingthe circuit.

FIGS. 10 and 11 show the rear interface module 28 in isolation from thepatching system 20. The rear interface module 28 includes a frame 140preferably made from bent sheet metal. The frame includes a front end142 positioned opposite from a rear end 144. The frame 140 also includesopposing top and bottom walls 146 and 148 that extend between the frontand rear ends 142 and 144. A rear wall 150 interconnects the top andbottom walls 146 and 148. As best shown in FIG. 11, the rear wall 150defines two vertically spaced-apart rows of openings 152.

The rear interface module 28 also includes two vertically spaced-apartrows of rear connectors 154 mounted at the rear wall 150. At leastportions of the rear connectors 154 preferably extend through thevertically spaced-apart openings 152. The rear connectors 154 preferablyinclude connecting pins 156 (shown in FIG. 11) that project generallytoward the front end 142 of the frame 140. The rear connectors 154 areheld in place by a board 158 (shown in FIG. 10) that is snap fit withinthe frame 140 and held against the rear connectors 154 by resilient tabs160. The board 158 preferably includes a plurality of openings forallowing the pins 156 to pass through.

The frame 140 includes the plurality of top and bottom ears 162 forallowing the frame 140 to be fastened (e.g., by conventional fastenerssuch as screws or bolts) to the rear of the card housing 24. The frame140 also includes top and bottom flanges 164 and 166 located at thefront end 142 of the frame 140. The top flange 164 extends downward fromthe top wall 146, and the bottom flange 166 extends upward from the topwall 148. The top and bottom flanges 164 and 166 define a plurality ofopenings for receiving fasteners (e.g., bolts or screws) used insecuring the card edge connectors 32 to the front end 142 of the frame140. As mounted at the front end 142 of the frame, the card edgeconnectors 32 are preferably aligned in a single row. Pins 168 of thecard edge connectors 130 preferably extend toward the rear end 144 ofthe frame 140 and project through a gap defined between the top andbottom flanges 164 and 166. In other embodiments, the card edgeconnectors 130 can be mounted inside the flanges 164 and 166 withreceptacles of the connectors 130 projecting forwardly through the gapbetween the flanges 164 and 166.

The rear connectors 154 are preferably arranged in an array having twovertically spaced apart rows. The pins 156 of the rear connectors 154are preferably connected to the pins 168 of the card edge connectors 32through the use of a flexible circuit board 170. The flexible circuitboard 170 is located between the top and bottom walls 146 and 148 of theframe 140. Preferably, the flexible circuit board 170 includes agenerally planar front portion 172 having electrical contacts thatcontact the pins 168 of the card edge connectors 32, and generallyplanar rear portion 174 having electrical contacts that engage the pins156 of the rear connectors 154. A flexed intermediate portion 175 curvesbetween the front and rear portions 172 and 174. A tracing diagram foreight pairs of vertically spaced-apart rear connectors 154 and theircorresponding card edge connectors 32 is shown in FIG. 14. In theembodiment shown, the rear connectors 154 each include nine pins 168,while the card edge connectors 32 each have a total of 20 pins. Theextra pins on the card edge connectors 32 allow for expansion and/ormodification of the type of rear connectors used.

The pins 156 and 168 respectively extend through plated through-holes156′ and 168′ of the flexible circuit board 170. Tracings 157electrically interconnect selected ones of the through holes 156′ withselected ones of the through holes 168′.

Referring now to FIGS. 12A-12D, various views of one of the card edgeconnectors 32 are shown. The card edge connector 32 includes adielectric housing 176 defining a central slot 178 sized for receivingone of the rear extensions 112 of the jack access cards 26. A plurality(e.g., 20) of opposing electrical contacts 180 are positioned within theslot 178. When the rear extension 112 of the jack access card 126 isinserted within the slot 178, the electrical contacts 180 engage thecard edge contacts 30 of the jack access card 26. In this manner, anelectrical connection is provided between the jack access card 26 andthe card edge connector 32.

The electrical contacts 180 are connected to the pins 168 that provideelectrical connections with the flexible circuit board 170. As shown inFIGS. 12B-12D, the pins 168 project transversely outward from a backside of the housing 176. The housing 176 also defines top and bottomscrew openings 182 and 184 for allowing the card edge connector to befastened to the frame 140.

FIGS. 13A-13D illustrate various views of one of the rear connectors154. As shown in 13A-13D, the rear connector 154 comprises a nine-pinD-subminiature type connector. The connector 154 includes a dielectricmember 186. The pins 156 project outward from one side of the dielectricmember 186, while a D-type fitting 188 projects outward from the otherside of the dielectric member 186. The D-fitting 188 comprises a femalefitting having a plurality of receptacles 190. However, it will beappreciated that in alternative embodiments 25 pin D-type fittings, AT&T110 D-type connectors, EDAC-90 connectors, EDAC-120 connectors, EDAC-56connectors, co-axial connectors, AMP-Champ 50 pin connectors, SVHSconnectors and QCP-type connectors, as well as other types ofconnectors, could also be used.

It will be appreciated that the modular nature of the rear interfacemodule 28 allows the entire module 28 to be disconnected from thechassis 22 and replaced with another module (e.g., a module having adifferent type of rear connector). In this manner, a user can easilymodify the array of rear connectors so as to accommodate different typesof transmitting and receiving equipment. Thus, user flexibility forcable termination connector options is improved.

FIG. 15 illustrates an alternative rear interface module 28′ adapted tobe connected to the chassis 22. The interface module 28′ is an eightcircuit module ( i.e., the module includes eight card edge connectors32′ and eight pairs of rear connectors 154′). Preferably, four of themodules 28′ would be removably mounted at the back end of the cardhousing 24 (shown in FIGS. 1B and 2). In this manner, flexibility forcable termination connector options is further enhanced by allowingselected groups of the connectors to be changed/replaced withoutdisturbing others of the connectors. It will be appreciated that othersized modules could also be used. By way of non-limiting example, one,two, four and sixteen circuit modules could be used.

With regard to the foregoing description, it is to be understood thatchanges can be made in detail, especially in matters of the constructionmaterials employed and the shape, size and arrangement of the partswithout departing from the scope of the present invention. It isintended that the specification and the depicted aspects be consideredexemplary only, with a true scope and spirit of the invention beingindicated by the broad meaning of the following claims.

What is claimed is:
 1. A telecommunications patching system adapted foruse with a plurality of patch cords including patch plugs, the patchingsystem comprising: a chassis including a card housing having a front endpositioned opposite from a rear end, the card housing including top andbottom walls extending between the front and rear ends, the top andbottom walls defining opposing sets of top and bottom slots, the slotshaving lengths that extend between the front and rear ends of the cardhousing, the slots being defined by edges which are substantiallyparallel and equidistant from each other along the lengths of the slots;a plurality of jack access cards adapted to be mounted through the frontend of the card housing, the jack access cards including circuit boardshaving top and bottom edges adapted to fit within the sets of top andbottom slots defined by the card housing, the jack access cards alsoincluding front interface pieces defining upper and lower patch plugports; rear connectors positioned at the rear end of the card housing,the rear connectors being electrically connected to contacts within theupper and lower patch plug ports by the circuit boards; and the housingincluding projections that project into the slots from the edges of theslots for positioning the circuit boards within the slots.
 2. Thepatching system of claim 1, wherein the projections include sets ofprojections corresponding to each slot, each set of projectionsincluding two spaced-apart first projections and a second projectionaligned between the first projections, the first projections extendinginto the slots in an opposite direction as compared to theircorresponding second projections.
 3. The patching system of claim 1,wherein the card housing of the chassis holds thirty-two of the jackaccess cards.
 4. A telecommunications system comprising: a chassisincluding a card housing having a front end positioned opposite from arear end, the card housing including top and bottom walls extendingbetween the front and rear ends, the top and bottom walls definingopposing sets of top and bottom slots; a plurality of cards mounted inthe card housing, the cards including circuit boards, the cards alsohaving top and bottom edges that fit within the sets of top and bottomslots defined by the card housing, the slots having lengths that extendbetween the front and rear ends of the card housing, the slots beingdefined by edges that extend along the lengths of the slots; firsttelecommunication line connection locations positioned adjacent thefront end of the card housing and second telecommunication lineconnection locations positioned adjacent the rear end of the cardhousing, the first and second telecommunication line connectionlocations being interconnected by signal pathways, and the circuitboards defining at least portions of the signal pathways between thefirst and second telecommunication line connection locations; and thehousing including projections that project into the slots from the edgesof the slots for positioning the circuit boards within the slots,wherein the projections includes sets of discrete projectionscorresponding to each slot, each set of projections including twospaced-apart first projections and a second projection aligned betweenthe first projections, the first projections extending into the slots inan opposite direction as compared to their corresponding secondprojections.
 5. The system of claim 4, wherein the card housing of thechassis holds thirty-two of the circuit boards.
 6. A method forinserting telecommunication components into a telecommunications system,the telecommunication components defining front ports for receivingtelecommunication plugs, wherein the telecommunications systemcomprises: a chassis including a housing having a front end positionedopposite from a rear end, the housing including top and bottom wallsextending between the front and rear ends, the top and bottom wallsdefining opposing sets of top and bottom slots, the slots having lengthsthat extend between the front and rear ends of the housing, the slotsbeing defined by edges that extend along the lengths of the slots; thehousing including projections that project into the slots from the edgesof the slots for positioning the telecommunication components within theslots, wherein the projections include sets of discrete projectionscorresponding to each slot, each set of projections including twospaced-apart first projections and a second projection aligned betweenthe first projections, the first projections extending into the slots inan opposite direction as compared to their corresponding secondprojections; and rear telecommunications connectors positioned adjacentthe rear end of the housing; the method comprising: sliding thetelecommunication components in a rearward direction within the top andbottom slots of the housing to electrically connect the front ports ofthe telecommunication components with the rear telecommunicationconnectors; and aligning the telecommunication components within the topand bottom slots through engagement with the projections.
 7. The methodof claim 6, wherein the projections align the telecommunicationcomponents within the slots such that the telecommunication componentsare aligned with the rear telecommunication connectors.
 8. Atelecommunications chassis comprising a housing having a front endpositioned opposite from a rear end, the housing including top andbottom walls extending between the front and rear ends, the top andbottom walls defining opposing sets of top and bottom slots, the slotshaving lengths that extend between the front and rear ends of thehousing, the slots being defined by edges that extend along the lengthsof the slots, the housing including projections that project into theslots from the edges of the slots, wherein the projections include setsof discrete projections corresponding to each slot, each set ofprojections including two spaced-apart first projections and a secondprojection aligned between the first projections, the first projectionsextending into the slots in an opposite direction as compared to theircorresponding second projections.
 9. the chassis of claim 8, wherein thehousing further comprises top and bottom flanges positioned at the frontend of the housing, the top and bottom flanges defining fasteneropenings for receiving fasteners.